This invention relates to a fixing structure of contact tails of an electrical connector having contacts in rows.
In the case of connecting a printed circuit to an external circuit, for example, a following method is usually employed. As shown in the exploded perspective view of FIG. 1a and the assembled view of FIG. 1b, a receptacle connector 2 is used, whose contact tails 1A and 1B are bent at right angles to directions into which a mating connector 5 is inserted into the receptacle connector 2. In this case, such L-shaped contact tails 1A and 1B are inserted into connecting apertures 3a of a printed circuit board 3. Thereafter, as shown in FIG. 1b, the connector 2 is fixed to the printed circuit board 3 by means of set screws 4 and further the contact tails are soldered to connecting conductive portions (not shown). When the mating plug connector 5 is inserted into the receptacle connector 2, the printed circuit board is connected to the external circuit.
In inserting the contact tails 1A and 1B into the connecting apertures 3a of the printed circuit board 3, automatic machines are often used on a large scale. For this purpose, the contact tails must be aligned with each other with a predetermined pitch and arranged in two rows spaced apart by a predetermined distance. If this condition is not fulfilled and contact tails 1A and 1B are not inserted into the connecting apertures 3a, such connectors are determined to be of inferior quality and automatically rejected.
In order to avoid this, a following method is generally carried out. As shown in a partial perspective view of FIG. 2a, a locater plate 6 (refer to again FIG. 1) is provided integrally with the connector at its connector extending portion and formed with press-fitting slits 6a of the same number as that of the contact tails in the one row and with the same pitch as that of the contact tails. The press-fitting slits 6a have lengths capable of receiving the contact tails and extend in transverse directions to the rows of the contact tails or longitudinal directions of the connector. On the other hand, the contact tails 1A and 1B are formed on both sides with holding projections 1a and 1b having the same extending distances in order to make a width of each contact tail at the projections somewhat larger than that of the press-fitting slit 6a. As shown in a partial perspective assembled view of FIG. 2b and a partial sectional view of FIG. 2c, the holding projections 1a and 1b of the contact tails 1A and 1B are press-fitted into the press-fitting slits 6a to fix the contact tails in the slits 6a, thereby preventing the contact tails 1A and 1B from being moved in the slits 6a due to external forces acting upon the contact tails 1A and 1B during transportation of the contacts.
With this fixing structure of the prior art, however, in most cases the contact tails 1B located near entrances of the slits tend to be subject to misalignment owing to external forces acting thereupon during transportation so that a predetermined distance between the rows of the contact tails is not maintained. It results in a number of connectors inferior in quality, which should be rejected.